QUANTITATIVE INFRARED STUDY OF ULTRATHIN MIS STRUCTURES BY GRAZING INTERNAL-REFLECTION

A very sensitive reflection technique well suited for infrared investigations of thin MIS structures is introduced. With this technique a nearly saturating reflectance drop from the Si-O vibration of a 1.3 nm oxide on silicon within a MIS structure was measured at 1240 cm-1. The analytic discussion of the sensitivity amplification of this technique shows that for silicon oxide a sensitivity amplification by a factor of 600 per reflection is feasible over the sensitivity of a transmission measurement. The analytic discussion is verified experimentally for the case of 12 nm silicon nitride film. A method that allows one to determine bond concentrations of thin films within MIS structures is given and tested for the case of hydrogen bonds in silicon nitride. © 1990 Springer-Verlag.